This invention relates to a color photographic silver halide material which can be developed to form a negative, and which comprises a support, at least one blue-sensitive silver halide emulsion layer which contains at least one yellow coupler, at least one green-sensitive silver halide emulsion layer which contains at least one magenta coupler, and at least one red-sensitive silver halide emulsion layer which contains at least one cyan coupler, at least 95% of the silver halide emulsions of which consist of AgCl, and which under scanning exposure and under analogue exposure is distinguished by sharp contrast which is independent of exposure time, and by a stable latent image.
In order to produce xe2x80x9cdigital printsxe2x80x9d, photographic material is inserted in scanning photographic exposure devices in which the exposure unit exposes the image information material on to the photographic material pixel by pixel, line by line or area by area, using directed light of high intensity (typically from lasers, from light-emitting diodes (LEDs), from devices which are termed DMDs (digital micromirror devices) or from comparable devices) and with very short exposure times per pixel (of the order of nano- to microseconds). At high densities in particular, the problem of line obliteration occurs. This is manifested in the image by a blurred depiction of the edges where there is a large difference in density (e.g. written characters) in the subject, and is a graphically described as xe2x80x9cbloomxe2x80x9d, xe2x80x9ccolor fringe formationxe2x80x9d, xe2x80x9cblurringxe2x80x9d, etc. This limits the usable range of densities of the photographic material. Therefore, photographic materials for the production of xe2x80x9cdigital printsxe2x80x9d of high image quality in scanning photographic exposure devices comprising LEDs or lasers have to exhibit only a slight extent of line obliteration at high color density (blackening).
It is known of from EP 774 689 that in order to achieve a higher color density without color fringe formation during pixel by pixel exposure with directed light of high intensity (typically from gas or diode lasers, from LEDs or from comparable devices) and at very short exposure times per pixel (typically of the order of nano- to microseconds), the gradation of the light-sensitive layers of the color negative paper used should be as steep as possible over the range of exposure times used.
It is known from EP 350 046 and from U.S. Pat. No. 5,500,329 that the gradation within the exposure range of seconds or milliseconds can be steepened by doping the silver halides with metal ions of transition metals of Group II and of Group VIII of the periodic table of the elements.
Moreover, it is known from EP 350 046 that doping of silver chloride or silver chloride-bromide emulsions with compounds of iridium and iron can reduce the fluctuation of photographic properties during a continuous chemical process.
Furthermore, it is known from JP 3 188 437, EP 476 602, JP 4 204 941, JP 4 305 644, EP 816 918 and EP 952 484 that doping silver chloride or silver chloride bromide emulsions with compounds of iridium and iron, in combination with other compounds or with other measures, can reduce the reciprocity failure of the emulsions.
It has been found, however, that when using these measures one of the most important photographic properties, namely the latent image stability, is not satisfactory.
The object of the present invention was to provide a material which is suitable for digital exposure and for analogue exposure and which is distinguished by steep gradation, irrespective of exposure times, and by stable latent image properties.
This object is surprisingly achieved if the color photographic material described at the outset contains at least one light-sensitive silver halide emulsion layer, which contains at least one compound of formulae (I) (II) and (III):
[IrClnF6-n]2xe2x88x92M2+xe2x80x83xe2x80x83(I) 
wherein n denotes 0 or an integer from 1 to 6 and M2+ denotes 1 or 2 cations with a total number of 2 positive charges,
[Fe(CN)6]mxe2x88x92Mm+xe2x80x83xe2x80x83(II) 
wherein m denotes 2 or 3 and M+ denotes 1 to 3 cations with a total number of m positive charges, 
wherein o denotes 0, 1 or 2 and R denotes an alkyl, aryl or aralkyl.
The emulsion which is used according to the invention is preferably produced either by a simple double-jet method, by a double-jet method with pre-precipitation and precipitation, or by a combined double-jet-redissolution method.
The silver halide emulsion preferably contains silver halide grains comprising at least two different zones, wherein the nucleus is produced by a double-jet method using an AgNO3 solution and a halide solution, essentially a chloride solution, and the precipitate is produced by redissolving a very fine-grained silver halide emulsion (a so-called micrate emulsion) on to the pre-precipitate.
In the double-jet method, the compounds of formulae (I) and (II) are preferably introduced via the halide solution.
In the double-jet-redissolution method, the compound of formula (I) is introduced via the micrate emulsion, and the compound of formula (II) is introduced via the halide solution during the double-jet precipitation or both compounds are introduced via the micrate emulsion.
The compound of formula (III) is preferably added before or during chemical ripening.
The following amounts are preferably used per mol Ag of silver halide emulsion:
10 nmol to 5 xcexcmol of the compound of formula (I)
10 nmol to 10 xcexcmol of the compound of formula (II)
0.1 nmol to 5 xcexcmol of the compound of formula (III).